模数

Our country present telephone network is mixed by digital mode and analogy mode, so our country present signaling system is at the stage of CAS and CCS commixture.

我国目前的电话网是数模混合的，所以我国目前的信令系统也处于随路信令和公共信道信令并存的阶段。

The key components in laser gyro is He-Ne ring laser, and the reciprocal action theory between light and medium is the base in studying the ring laser, use the Lamb half classical theory, and on the base of density matrix theory, the optical Brounch equation was established, which described the movement of amplifying medium atom in the ring syntonic cavity, and according to the medium polarize theory the self consistent equations was deduced, which describe the light intensity and phasic of the counter-propagating wave. On the basis of this equations, adopted the simulation software MATLAB and virtual instrument programming language LabWindows/CVI, we can do some simulated experiments in study the phenomenas such as amplify and dispersive characteristic of medium, mode pushing effection, burned hole effection and pattern competition, lock-in of frequency and the characteristic of light intensity and phasic of the counter-propagating wave in laser gyro.

激光陀螺的核心部件为He-Ne环形激光器，而掌握光与介质的相互作用理论是研究激光器的关键，采用拉姆半经典理论为主，在密度矩阵理论的基础上，推导环形谐振腔中描述He-Ne气体增益介质原子运动的光学布洛赫方程，运用介质极化理论得出描述激光陀螺反向行波的光强、位相所满足的自洽场方程组，在此基础上，运用MATLAB仿真软件和虚拟仪器编程语言LabWindows/CVI，对激光陀螺中的介质增益色散特性、频率牵引效应、烧孔效应及模竞争、闭锁效应及环激光的光强和相位特性进行仿真试验研究，并且运用全量子理论，对激光工作原理进行分析，得出二能级系统单模辐射场的光子数密度分布，得出激光场的光子统计分布，仿真激光场的动态建立过程。

Based on the modal superposition method and the exact solution of beam nature vibration, the motion equations of the simply supported and continuo...

基于模态叠加法和梁固有振动的精确解，建立了移动荷载作用下简支梁和连续梁的运动方程；利用样条最小二乘法逼近桥梁应变响应，由样条数值微分求得响应导数；再通过Tikhonov正则化方法结合奇异值分解技术得到了荷载识别的正则解。

The transformation between digital signal and DC voltage was made with D/A converser and high voltage amplifier; varactor s were used for tuning components; the bandpass filter was a combline microstrip line one, its dimension was presented.

采用数模转换器和高压运放实现数字信号与直流电压的转换；以变容二极管作为调谐元件；带通滤波器采用梳状微带线结构，并给出了结构参数。

The program, worked out with FORTRAN language, is a kind of mathematic model derived from the theory of plastoelastie crankle, and can be used for various computers.

该程序是根据弹塑性弯曲理论推导的数模，用FORTEN语言编制而成的，可在各类计算机上应用。

The Pinching problems are discussed on the sectional curvature of compact space-like pseudo-umbilical submanifolds M~n with parallel mean curvature vector in De Sitter space S~_p, and the theory of reduction of the codimension is obtained in De Sitter space through evaluating the Laplacian of square of the length.

讨论了De Sitter空间Snp+p中，具有平行平均曲率向量的紧致类空伪脐子流形Mn的截面曲率的拼挤问题，通过估计第二基本形式模长平方的Laplacian，得到了De Sitter空间中的余维数压缩定理。

Using MK- 801 double board computer and digit to anolog interface circuit as hardwar, de-sign and a set of temperature autocortrol system , sassociating with DWK- 702 instrument of tempera-ture fine control, applying to production technique of T1 -superrconductors and making this automa-tize.

采用MK－801双板计算机及其数模接口电路为硬件，设计并制造一套温度自动控制系统，联合DWK－702精密温度控制装置，对T1系超导材料的烧制过程进行自动控制，使这一过程自动化、程序化、并提高了温度控制精度。

It introduces normal families, including equicontinuity, Arzela's theorem, Montel's and Marty's theorems, Zalcman's lemma; univalent functions, including Koebe's and de Branges' theorems; quasiconformal mappings, including conformal length, extremal length, geometric, analytic and metric definitions, quasiconformal extension, distortion theorem, quasicircle; iteration of rational functions, including fixed points, the Fatou and Julia sets, periodic points, Siegel disks, the Hausdorff measure and dimension, etc.

具体为：正规族，包括等度连续性、Arzela定理、Montel和Marty正规定则、Zalcman引理；单叶函数，包括Koebe定理和de Branges定理；拟共形映照，包括共形模、极值长度、几何、分析和距离定义、拟共形延拓、偏差定理，拟圆周等；有理函数的迭代，包括不动点、Fatou集和Julia集、周期点、Siegel盘、Hausdorff测度和维数，等等。在教学内容上充分体现综合性、前沿性。

This high voltage electrostatic precipitation controller has 7 channels of analog input,2 channels of analog output, 12 digital inputs and 16 digital outputs. The analog input includes primary current, secondary current, primary voltage, secondary voltage, etc. Controller uses MAX 187 as the A/D converter, which ensure the sampling speed and the conversion precision in the same time. The processor unit is RCM2250 module. Rabit 2000 processor, a 128K SRAM and a 256K Flash Rom are integrated in RCM2250, which improves the performance of pricipitation controller. MAX504 is used to produce the 4~20mA current output.

模拟量输入采集的信号有升压变压器一次电流、一次电压、二次电流、二次电压等，采用12位逐次比较式A/D转换器MAX187，兼顾采样速率和转换精度；中央处理单元采用以8位嵌入式处理器Rabbit2000为基础的RCM2250模块，外扩128KSRAM和256K Flash ROM，内部资源丰富，提高了控制器的整体性能；模拟量输出采用内带基准源的10位电压输出数模转换器MAX504，实现了标准4～20mA电流信号输出；控制器通过控制算法在相应开关量点上输出可控硅的触发脉冲。

A candidate should be able to explain elementary circuit systems performance, such as amplifier, comparator, DAC circuit, etc.

预测并解释电路系统的性能，如可放大器，比较器，数模转换电路等。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。